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mmunological functions of liver sinusoida endothelial cells

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Cellular & molecular Immunology 2016年第3期13卷 347-353页

作者： Percy A Knolle dirk Wohlleber Institute of molecular Immunology and Experimental Oncology Klinikum Munchen rechts der Isar Technische Universitat Munchen Munchen 81675 Germany Institute of Experimental Immunology Universitatsklinikum Bonn Universitat Bonn Bonn Germany

Liver sinusoidal endothelial cells （LSECs） line the liver sinusoids and separate passenger leukocytes in the sinusoidal lumen from hepatocytes. LSECs further act as a platform for adhesion of various liver-resident immune cell populations such as Kupffer cells, innate lymphoid cells or liver dendritic cells. In addition to having an extraordinary scavenger function, LSECs possess potent immune functions, serving as sentinel cells to detect microbial infection through pattern recognition receptor activation and as antigen （cross）-presenting cells. LSECs cross-prime naive CD8 T cells, causing their rapid differentiation into memory T cells that relocate to secondary lymphoid tissues and provide protection when they re-encounter the antigen during microbial infection. Cross-presentation of viral antigens by LSECs derived from infected hepatocytes triggers local activation of effector CD8 T cells and thereby assures hepatic immune surveillance. The immune function of LSECs complements conventional immune-activating mechanisms to accommodate optimal immune surveillance against infectious microorganisms while preserving the integrity of the liver as a metabolic organ.

关键词： CD8 T cells cross-presentation liver LSEC

membrane-destabilizing ionizable phospholipids: Novel components for organ-selective mRNA delivery and CRISPR-Cas gene editing

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Signal Transduction and Targeted Therapy 2021年第6期6卷 1643-1645页

作者： Ning meng dirk Grimm Department of Infectious Diseases/Virology Medical FacultyUniversity of HeidelbergHeidelbergGermany BioQuant University of HeidelbergHeidelbergGermany German Center for Infection Research(DZIF)and German Center for Cardiovascular Research(DZHK) partner site HeidelbergHeidelbergGermany

In a new study published in Nature materials,Liu et al.1 report a novel design of lipid nanoparticles(LNPs)in which multi-tailed ionizable phospholipids(iPhos)constitute the active component,and which facilitates endosomal escape and thus improves delivery of mRNA and/or single-guide(sg)RNA for in vivo gene *** composed of the best-performing iPhos and different helper lipids_zwitterionic lipids,ionizable cationic lipids and permanently cationic lipids-achieved selective organ targeting(SORT)and organ-specific CRISPR-Cas9 gene editing in spleen,liver,and lungs of mice,respectively.

关键词： spleen editing cationic

Authigenic gypsum found in gas hydrate-associated sediments from Hydrate Ridge, the eastern North Pacific

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Science China Earth Sciences 2004年第3期47卷 280-288页

作者： Erwin Suess dirk Rickert Department of marine Environmental Geology Research Centre of Marine Geology University of Kiel Kiel D-24148 Germany Department of Marine Environmental Geology Research Centre of Marine Geology University of Kiel Kiel D-24148 Germany

Characteristic gypsum micro-sphere and granular mass were discovered by bin-ocular microscope in the gas hydrate-associated sediments at cores SO143-221 and SO143/TVG40-2A respectively on Hydrate Ridge of Cascadia margin, the eastern North Pacific. XRD patterns and EPA analyses show both micro-sphere and granular mass of the crystals have the typical peaks and the typical main chemical compositions of gypsum, although their weight percents are slightly less than the others in the non-gas hydrate-associated marine regions. SEm pictures show that the gypsum crystals have clear crystal boundaries, planes, edges and cleav-ages of gypsum in form either of single crystal or of twin crystals. In view of the fact that there are meanwhile gas hydrate-associated authigenic carbonates and SO42--rich pore water in the same sediment cores, it could be inferred reasonably that the gypsums formed also authigenically in the gas hydrate-associated environment too, most probably at the interface between the down-ward advecting sulfate-rich seawater and the below gas hydrate, which spilled calcium during its formation on Hydrate Ridge. The two distinct forms of crystal intergrowth, which are the granular mass of series single gypsum crystals at core SO143/TVG40-2A and the microsphere of gypsum crystals accompanied with detrital components at core SO143-221 respectively, indicate that they precipitated most likely in different interstitial water dynamic environments. So, the distinct authigenic gypsums found in gas hydrate-associated sediments on Hydrate Ridge could also be believed as one of the parameters which could be used to indicate the presence of gas hydrate in an unknown marine sediment cores.

关键词： authigenic gypsum, gas hydrate-associated sediment, Hydrate Ridge, eastern North Pacific.

Detoxification of ferrocyanide in a soil–plant system

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Journal of Environmental Sciences 2019年第3期31卷 54-64页

作者： Tsvetelina Dimitrova Frank Repmann dirk Freese Brandenburg University of Technology Cottbus-Senftenberg

The detoxification of iron cyanide in a soil–plant system was investigated to assess the total cyanide extracted from contaminated soil and allocated in the leaf tissue of willow trees(Salix caprea). They were grown in soil containing up to 1000 mg/kg dry weight(dw) of cyanide(CN),added as ^(15)N-labeled potassium ferrocyanide and prepared with a new method for synthesis of labeled iron cyanides. CN content and ^(15)N enrichment were monitored weekly over the exposure in leaf tissue of different age. The ^(15)N enrichment in the young and old leaf tissue reached up to 15.197‰ and 9063‰, respectively; it increased significantly over the exposure and with increasing exposure concentrations(p mulation in the old leaf tissue was higher, compared to the young leaf tissue(p ment in the two tissue types did not differ statistically. This indicates a non-uniform CN accumulation but a uniform ^(15)N allocation throughout the leaf mass. Significant differences were detected between the measured CN content and the C^(15)N content, calculated from the ^(15)N enrichment(p moval and detoxification under the experimental conditions.

关键词： Iron cyanide Detoxification Exposure Phytoremediation

Deep Drawing with Local Hardening on Digital multi-axis Servo Press

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Acta metallurgica Sinica(English Letters) 2015年第12期28卷 1490-1495页

作者： Sebastian Kriechenbauer Reinhard mauermann dirk Landgrebe Fraunhofer IWU

The paper discusses a new drawing technology, based on a synchronized movement of ram and cushion with multiple bending operations in alternating directions called ＂bi-directional deep drawing（BDD）.＂ The goal is to avoid local thinning by strengthening the weak point using local hardening. BDD operations are realized before the conventional deep drawing process. This results in a local strain hardening at the weak point of the workpiece, which is usually located at the bottom punch radius. Two major aspects have to be given attention due to the high number of process parameters. On the one hand, for process design, it is helpful to have a tool by means of which it is possible to simultaneously create both the machine program for the servo press and the initial configuration for the process simulation. From the authors＇ point of view, this complexity can only be represented by a numerical analysis method, on the other hand. Consequently, both aspects are given attention in this paper.

关键词： Bi-directional deep drawing(BDD) Local hardening Servo press Pulsation

Experimental and computational analysis of the coolant distribution considering the viscosity of the cutting fluid during machining with helical deep hole drills

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Advances in manufacturing 2022年第2期10卷 235-249页

作者： Ekrem Oezkaya Sebastian michel dirk Biermann Institute of machining Technology Dortmund University of Technology(TU Dortmund)Dortmund 44227Germany

An experimental analysis regarding the distribution of the cutting fluid is very difficult due to the inaccessibility of the contact zone within the bore ***,suitable simulation models are necessary to evaluate new tool designs and optimize drilling *** this paper the coolant distribution during helical deep hole drilling is analyzed with high-speed *** particles are added to the cutting fluid circuit bya developed high-pressure mixing *** the evaluation of suitable particle size,particle concentration and coolant pressure,a computational fluid dynamics(CFD)simulation is validated with the experimental *** comparison shows a very good model quality with a marginal difference for the flow velocity of 1.57%between simulation and *** simulation considers the kinematic viscosity of the *** results show that the fluid velocity in the chip flutes is low compared to the fluid velocity at the exit of the coolant channels of the tool and drops even further between *** velocity and the flow pressure directly at the cutting edge decrease to such an extent that the fluid cannot generate a sufficient cooling or *** the CFD simulation a deeper understanding of the behavior and interactions of the cutting fluid is *** on these results further research activities to improve the coolant supply can be carried out with great potential to evaluate new tool geometries and optimize the machining process.

关键词： Computational fluid dynamics(CFD)analysis:Viscosity-Tracermicro particles Fluidbehavior Helical deep hole drilling

Assessment of wear micromechanisms on a laser textured cemented carbide tool during abrasive-like machining by FIB/FESEm

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Friction 2021年第3期9卷 656-664页

作者： Shiqi FANG dirk BÄHRE Luis LLANES Institute of Production Engineering Saarland UniversitySaarbrücken 66123Germany CIEFmA-Department of materials Science and Engineering EEBE-Campus Diagonal BesòsUniversitat Politècnica de CatalunyaBarcelona 08019Spain

The combined use of focused ion beam(FIB)milling and field-emission scanning electron microscopy inspection(FESEm)is a unique and successful approach for assessment of near-surface phenomena at specific and selected *** this study,a FIB/FESEm dual-beam platform was implemented to docment and analyze the wear micromechanisms on a laser-surface textured(LST)hardmetal(Hm)*** particular,changes in surface and microstructural integrity of the laser-sculptured pyramids(effective cutting microfeatures)were characterized after testing the LST-Hm tool against a steel workpiece in a workbench designed to simulate an external honing *** was demonstrated that:(1)laser-surface texturing does not degrade the intrinsic surface integrity and tool effectiveness of Hm pyramids;and(2)there exists a correlation between the wear and loading of shaped pyramids at the local ***,the enhanced performance of the laser-textured tool should consider the pyramid geometry aspects rather than the microstructure assemblage of the Hm grade used,at least for attempted abrasive applications.

关键词： focused ion beam(FIB) field-emission scanning electron microscopy inspection(FESEm) cemented carbides laser surface texturing abrasive machining processes wear

Experimental and Theoretical Study on Piezoresistive Behavior of Compressible melamine Sponge modified by Carbon-based Fillers

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Chinese Journal of Polymer Science 2022年第11期40卷 1503-1512页

作者： Xiao-Ling Luo dirk W.Schubert Institute of Polymer materials Friedrich-Alexander-University Erlangen-NurembergMartensstr.7Erlangen91058Germany KeyLab Advanced Fiber Technology Bavarian Polymer InstituteDr.Mack-Strasse 77Fürth90762Germany

High-performance compression sensors have been playing an increasingly important role in human motion detection,health monitoring and human-machine interfaces over recent ***,it remains a great challenge to develop theoretical models providing practical guidance to the sensor ***,carbon black(CB),carbon nanotubes(CNTs)and graphene nanoplatelets(GNPs)were respectively incorporated into porous melamine sponges by a facile approach of dip-coating to fabricate compression *** compression-resistance tests show that the compressibility,stability and piezoresistive sensitivity of sensors could be tailored by the filler type and concentration.A model considering the number of conductive pathways(NCP)is given to describe the relationship between the resistance change and applied compression,showing extremely good agreement with the experimental ***,the correlation between the equivalent filler volume fraction and conductivity is described by the other two models proposed by mcLachlan and Kirkpatrick,revealing the electrical percolation thresholds(Φc)for the conductive systems under *** the three fillers,CB particles endowed the composite with the best piezoresistive sensitivity but the largestΦc due to its small size and aspect ratio.A combination of experimental study and theoretical model opens up a way of further understanding the piezoresistive sensing behavior as well as optimizing the electrical property and piezoresistivity of compressive conductive polymer composite.

关键词： Compression sensor melamine sponge model Piezoresistivity

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维生素D代谢物有助于母猪分娩过程

国外畜牧学（猪与禽） 2024年第1期44卷 12-13页

作者： Katia Pedrosa Kathrin Buehler Jan dirk Van der Klis 张相鑫(译) 王晶晶(校) 孟祥光(制图) 不详

维生素D是一种重要的营养物质,母猪在妊娠后期和哺乳期对其需要量非常高。本文概述了维生素D对母猪分娩的影响,提出可以在常规添加维生素D之外补充1,25-二羟基维生素D3糖苷,以缩短分娩时间,减少分娩过程中的人为干预,减少死胎数。

关键词：维生素D 1 25-二羟基维生素D3糖苷分娩